5.2 Energy-Efficient Low-Noise CMOS Image Sensor with Capacitor Array-Assisted Charge-Injection SAR ADC for Motion-Triggered Low-Power IoT Applications

As IoT is increasingly integrated into our everyday life, the demand for different sensor modalities, especially imaging, is rising. IoT imagers are often compact and have small form-factor batteries and thus must be designed with both low power (improving battery life) and high image quality (maximizing utility). Previously reported sensors [1, 2], along with this work, adopt motion-detection (MD) triggering of full-array capture where MD is performed on a heavily subsampled frame to enable continuous low-power operation. MD limits energy-hungry full-array captures to cases where activity is detected. To further reduce power consumption, the full-frame capture energy itself needs to be addressed, which is typically dominated by the ADC.